A sharp increase in global gold prices has reignited a mining rush in Brazil's Amazon rainforest, leading to accelerated deforestation in protected areas and dangerous levels of mercury contamination, according to officials and experts.
Illegal Mining Expands in Conservation Zones
A recent study by Amazon Conservation and Brazilian nonprofit Instituto Socioambiental reveals that illegal mining operations have caused extensive clear-cutting in three conservation areas within the Xingu region, one of the world's largest protected forest expanses spanning Para and Mato Grosso states. The analysis combined satellite imagery with ground research to document the destruction.
The Terra do Meio Ecological Station recorded its first illegal mining in September 2024, with mining-related deforestation expanding to 30 hectares (74 acres) by end of 2025. At the Altamira National Forest, illegal mining caused 832 hectares (2,056 acres) of deforestation between 2016 and September 2025. A new mining front that emerged in 2024 grew to 36 hectares (89 acres) by October 2025, accounting for nearly half of the mining-related deforestation that year. Satellite monitoring also detected a clandestine airstrip at the Nascentes da Serra do Cachimbo Biological Reserve, where illegal mining expanded from 2 hectares (5 acres) to at least 26.8 hectares (66 acres) in 2025.
Most Mining Deforestation Is Illegal
Amazon Conservation, Earth Genome, and the Pulitzer Center developed Amazon Mining Watch in 2023, a platform tracking mining across the Amazon since 2018. About 496,000 hectares (1,225,640 acres) of rainforest have been cleared for mining, including 223,000 hectares (551,045 acres) in the Brazilian Amazon. Amazon Conservation estimates 80% of mining-related deforestation in Brazil is likely illegal. While mining is a small driver of overall deforestation, which is largely linked to agribusiness, it disproportionately affects protected areas and Indigenous territories.
“What makes mining particularly problematic is that it targets protected areas and Indigenous territories,” said Matt Finer, director of Amazon Conservation’s Monitoring of the Andes Amazon program. Protecting Indigenous territories is seen as an effective way to curb deforestation in the Amazon, the world’s largest rainforest and a key climate regulator.
Enforcement Challenges Persist
In 2023, Brazilian authorities cracked down on illegal gold mining in the Yanomami Indigenous territory in Roraima state, after a surge caused a humanitarian and health crisis. Annual growth in newly mined areas fell sharply after that year, but mining has not been fully eliminated. Localised enforcement has not curbed illegal mining across the Amazon, as miners often relocate or resume operations once authorities leave. Federal prosecutor André Luiz Porreca described enforcement as a “cat-and-mouse game.”
“Last year, I took part in an operation that destroyed more than 500 dredges on an Indigenous land. The following week, Indigenous people showed me photos proving the miners had already returned,” Porreca said. He noted that illegal gold mining is financed by Brazil’s largest criminal organizations, including Red Command and First Capital Command, which operate in about a third of cities in the Brazilian Amazon. While enforcement eased pressure in Yanomami territory, illegal mining has intensified elsewhere, especially on the Kayapo Indigenous land, where roughly 7,940 hectares (19,620 acres) have been cleared.
Mercury Contamination Worsens
Record-breaking gold prices, driven by investor demand for safe assets, have incentivized illegal mining. “It’s basic market logic. With more buyers, there are more people exploiting gold,” Porreca said, adding that Brazil’s mineral export control system remains weak. Environmental damage extends beyond deforestation, as illegal mining dumps mercury into rivers, contaminating waterways and fish consumed by riverine and Indigenous communities.
In April, Porreca submitted a report to the Inter-American Commission on Human Rights citing a Fiocruz study that found 21.3% of fish sold in Amazon public markets exceeded WHO mercury limits. Children ages 2 to 4 consumed mercury at levels up to 31 times higher than recommended.
Government Response
Under Brazilian law, mining is prohibited on Indigenous lands. The Ministry of Indigenous Peoples stated that combating illegal mining is a priority for President Luiz Inácio Lula da Silva’s administration, requiring dismantling criminal networks. The Ministry of Environment acknowledged mercury contamination as a persistent problem and said it is expanding scientific monitoring while supporting enforcement. Brazil’s Federal Police did not respond to requests for comment.
